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Molecules (Basel, Switzerland) Aug 2021In this work, we propose the utilization of scCO to impregnate ibuprofen into the mcl-PHA matrix produced by subs. (DSM 19603). The biopolymer has adhesive properties,...
In this work, we propose the utilization of scCO to impregnate ibuprofen into the mcl-PHA matrix produced by subs. (DSM 19603). The biopolymer has adhesive properties, is biocompatible and has a melting temperature of 45 °C. Several conditions, namely, pressure (15 and 20 MPa) and impregnation time (30 min, 1 h and 3 h) were tested. The highest ibuprofen content (90.8 ± 6.5 mg of ibuprofen/g) was obtained at 20 MPa and 40 °C, for 1 h, with an impregnation rate of 89 mg/(g·h). The processed mcl-PHA samples suffered a plasticization, as shown by the decrease of 6.5 °C in the T, at 20 MPa. The polymer's crystallinity was also affected concomitantly with the matrices' ibuprofen content. For all the impregnation conditions tested the release of ibuprofen from the biopolymer followed a type II release profile. This study has demonstrated that the mcl-PHA produced by has a great potential for the development of novel topical drug delivery systems.
Topics: Adhesiveness; Carbon Dioxide; Drug Carriers; Drug Liberation; Ibuprofen; Polyhydroxyalkanoates; Temperature
PubMed: 34443357
DOI: 10.3390/molecules26164772 -
Journal of Applied Microbiology Nov 2022Phenazines, such as phenazine-1-carboxylic acid (PCA), phenazine-1-carboxamide (PCN), 2-hydroxyphenazine-1-carboxylic acid (2-OH-PCA), 2-hydroxyphenazine (2-OH-PHZ), are...
AIMS
Phenazines, such as phenazine-1-carboxylic acid (PCA), phenazine-1-carboxamide (PCN), 2-hydroxyphenazine-1-carboxylic acid (2-OH-PCA), 2-hydroxyphenazine (2-OH-PHZ), are a class of secondary metabolites secreted by plant-beneficial Pseudomonas. Ps. chlororaphis GP72 utilizes glycerol to synthesize PCA, 2-OH-PCA and 2-OH-PHZ, exhibiting broad-spectrum antifungal activity. Previous studies showed that the addition of dithiothreitol (DTT) could increase the phenazines production in Ps. chlororaphis GP72AN. However, the mechanism of high yield of phenazine by adding DTT is still unclear.
METHODS AND RESULTS
In this study, untargeted and targeted metabolomic analysis were adopted to determine the content of metabolites. The results showed that the addition of DTT to GP72AN affected the content of metabolites of central carbon metabolism, shikimate pathway and phenazine competitive pathway. Transcriptome analysis was conducted to investigate the changed cellular process, and the result indicated that the addition of DTT affected the expression of genes involved in phenazine biosynthetic cluster and genes involved in phenazine competitive pathway, driving more carbon flux into phenazine biosynthetic pathway. Furthermore, genes involved in antioxidative stress, phosphate transport system and mexGHI-opmD efflux pump were also affected by adding DTT.
CONCLUSION
This study demonstrated that the addition of DTT altered the expression of genes related to phenazine biosynthesis, resulting in the change of metabolites involved in central carbon metabolism, shikimate pathway and phenazine competitive pathway.
SIGNIFICANCE AND IMPACT OF THE STUDY
This work expands the understanding of high yield of phenazine by the addition of DTT and provides several targets for increasing phenazine production.
Topics: Pseudomonas chlororaphis; Glycerol; Antifungal Agents; Dithiothreitol; Transcriptome; Phenazines; Metabolomics; Gene Expression Profiling; Carbon; Phosphates; Bacterial Proteins
PubMed: 35870153
DOI: 10.1111/jam.15727 -
Frontiers in Microbiology 2023The spectral distribution of light (different wavelength) has recently been identified as an important factor in the dynamics and function of leaf-associated microbes....
BACKGROUND
The spectral distribution of light (different wavelength) has recently been identified as an important factor in the dynamics and function of leaf-associated microbes. This study investigated the impact of different wavelength on three commercial biocontrol agents (BCA): (BA), (PC), and (SG).
METHODS
The impact of light exposure on sole carbon source utilization, biofilm formation, and biosurfactant production by the selected BCA was studied using phenotypic microarray (PM) including 190 sole carbon sources (OmniLog®, PM panels 1 and 2). The BCA were exposed to five monochromatic light conditions (420, 460, 530, 630, and 660 nm) and darkness during incubation, at an intensity of 50 μmol m s.
RESULTS
Light exposure together with specific carbon source increased respiration in all three BCA. Different wavelengths of light influenced sole carbon utilization for the different BCA, with BA and PC showing increased respiration when exposed to wavelengths within the blue spectrum (420 and 460 nm) while respiration of selected carbon sources by SG increased in the presence of red light (630 and 660 nm). Only one carbon source (capric acid) generated biosurfactant production in all three BCA. A combination of specific wavelength of light and sole carbon source increased biofilm formation in all three BCA. BA showed significantly higher biofilm formation when exposed to blue (460 nm) and green (530 nm) light and propagated in D-sucrose, D-fructose, and dulcitol. PC showed higher biofilm formation when exposed to blue light. Biofilm formation by SG increased when exposed to red light (630 nm) and propagated in citraconic acid.
CONCLUSION
To increase attachment and success in BCA introduced into the phyllosphere, a suitable combination of light quality and nutrient conditions could be used.
PubMed: 36819051
DOI: 10.3389/fmicb.2023.1087639 -
Applied and Environmental Microbiology Feb 2020Bacterial rhizosphere colonization is critical for phytobeneficial rhizobacteria such as phenazine-producing spp. To better understand this colonization process,...
Bacterial rhizosphere colonization is critical for phytobeneficial rhizobacteria such as phenazine-producing spp. To better understand this colonization process, potential metabolic and genomic determinants required for rhizosphere colonization were identified using a collection of 60 phenazine-producing strains isolated from multiple plant species and representative of the worldwide diversity. and (potato) were used as host plants. Bacterial rhizosphere colonization was measured by quantitative PCR using a newly designed primer pair and TaqMan probe targeting a conserved region of the phenazine biosynthetic operon. The metabolic abilities of the strains were assessed on 758 substrates using Biolog phenotype microarray technology. These data, along with available genomic sequences for all strains, were analyzed in light of rhizosphere colonization. Strains belonging to the subgroup colonized the rhizospheres of both plants more efficiently than strains belonging to the subgroup. Metabolic results indicated that the ability to use amines and amino acids was associated with an increase in rhizosphere colonization capability in and/or in The presence of multiple genetic determinants in the genomes of the different strains involved in catabolic pathways and plant-microbe and microbe-microbe interactions correlated with increased or decreased rhizosphere colonization capabilities in both plants. These results suggest that the metabolic and genomic traits found in different phenazine-producing strains reflect their rhizosphere competence in and Interestingly, most of these traits are associated with similar rhizosphere colonizing capabilities in both plant species. Rhizosphere colonization is crucial for plant growth promotion and biocontrol by antibiotic-producing spp. This colonization process relies on different bacterial determinants which partly remain to be uncovered. In this study, we combined a metabolic and a genomic approach to decipher new rhizosphere colonization determinants which could improve our understanding of this process in spp. Using 60 distinct strains of phenazine-producing spp., we show that rhizosphere colonization abilities correlated with both metabolic and genomic traits when these bacteria were inoculated on two distant plants, and Key metabolic and genomic determinants presumably required for efficient colonization of both plant species were identified. Upon further validation, these targets could lead to the development of simple screening tests to rapidly identify efficient rhizosphere colonizers.
Topics: Arabidopsis; Genome, Bacterial; Phenazines; Pseudomonas; Rhizosphere; Solanum tuberosum
PubMed: 31811040
DOI: 10.1128/AEM.02443-19 -
Journal of Agricultural and Food... Dec 2020Phenazine-1-carboxylic acid (PCA), the primary active ingredient of Shenqinmycin, was awarded the China Pesticide Certificate in 2011 due to its excellent antibacterial...
Phenazine-1-carboxylic acid (PCA), the primary active ingredient of Shenqinmycin, was awarded the China Pesticide Certificate in 2011 due to its excellent antibacterial action. Phenazine-1-carboxamide (PCN) is a derivative of PCA, which is modified by the gene, and its anti-bacterial effect is better than that of PCA. At present, PCN can be produced via fermentation using an opportunistic pathogen, . Qlu-1 is an environmentally friendly strain of that can produce phenazine derivatives. We replaced the gene with the gene from to achieve PCN accumulation. Different strategies were used to enhance PCN production: knocking out of negative regulatory factors, enhancing the shikimate pathway by gene overexpression and gene knocking, and using fed-batch fermentation. Finally, an engineered strain of was produced, which produced 11.45 g/L PCN. This achievement indicates that Qlu-1 could be modified as a potential microbial cell factory for PCN production by metabolic engineering.
Topics: Bacterial Proteins; Metabolic Engineering; Multigene Family; Phenazines; Pseudomonas aeruginosa; Pseudomonas chlororaphis
PubMed: 33287542
DOI: 10.1021/acs.jafc.0c05746 -
FEMS Microbiology Letters Sep 2019Pseudomonas chlororaphis PA23 is a biocontrol agent that, in addition to producing antifungal compounds, synthesizes polyhydroxyalkanoate (PHA) polymers as a carbon and...
Pseudomonas chlororaphis PA23 is a biocontrol agent that, in addition to producing antifungal compounds, synthesizes polyhydroxyalkanoate (PHA) polymers as a carbon and energy sink. Quorum sensing (QS) and the anaerobic regulator (ANR) are required for PA23-mediated fungal suppression; however, the role of these regulators in PHA production is unknown. Strains lacking either QS or ANR accumulated less PHA polymers when propagated on Ramsay's minimal medium (RMM) with glucose or octanoate as the carbon source. In the acyl-homoserine lactone (AHL)-deficient background, all six of the genes in the pha locus (phaC1, phaC2, phaZ, phaD, phaF, phaI) showed reduced expression in RMM glucose, and all except phaC2 were repressed in RMM octanoate. Although changes in gene activity were observed in the anr mutant, they were less pronounced. Analysis of the promoter regions for QS- and ANR-binding consensus sequences revealed putative phzboxes upstream of phaZ and phaI, but no anr boxes were identified. Our findings indicate that altered pha gene expression likely contributes to the lower PHA accumulation in the QS- and ANR-deficient strains, which may be in part indirectly mediated. This study is the first to show that mcl-PHA production is under QS and ANR control.
Topics: Anaerobiosis; Bacterial Proteins; Base Sequence; Caprylates; Gene Expression Regulation, Bacterial; Glucose; Polyhydroxyalkanoates; Pseudomonas chlororaphis; Quorum Sensing; Trans-Activators
PubMed: 31688920
DOI: 10.1093/femsle/fnz223 -
Environmental Science & Technology Oct 2021Strategies to reduce crop losses due to drought are needed as climate variability affects agricultural productivity. Wheat ( var. Juniper) growth in a...
Strategies to reduce crop losses due to drought are needed as climate variability affects agricultural productivity. Wheat ( var. Juniper) growth in a nutrient-sufficient, solid growth matrix containing varied doses of CuO, ZnO, and SiO nanoparticles (NPs) was used to evaluate NP mitigation of drought stress. NP amendments were at fertilizer levels, with maxima of 30 Cu, 20 Zn, and 200 Si (mg metal/kg matrix). Seeds of this drought-tolerant cultivar were inoculated with O6 (O6) to provide a protective root microbiome. An 8 day drought imposed on 14 day-old wheat seedlings decreased shoot and root mass, shoot water content, and the quantum yield of photosystem II when compared to watered plants. O6 root colonization was not impaired by drought or NPs. A dose-dependent increase in the Cu, Zn, and Si from the NPs was observed from analysis of the rhizosphere solution, and this process was not affected by drought. Consequently, fertilizer concentrations of the NPs did not further improve drought tolerance in wheat seedlings under the growth conditions of adequate mineral nutrition and the presence of a beneficial microbiome. These findings suggest that potential NP benefits in promoting plant drought tolerance occur only under certain environmental conditions.
Topics: Droughts; Nanoparticles; Nutrients; Plant Roots; Seedlings; Silicon Dioxide; Triticum; Zinc Oxide
PubMed: 34009961
DOI: 10.1021/acs.est.1c00453 -
Journal of Basic Microbiology Jul 2022In the present study, nonrhizobial endophytes were isolated from Pisum sativum and Cicer arietinum from Haryana, India. A total of 355 bacterial endophytes were screened...
In the present study, nonrhizobial endophytes were isolated from Pisum sativum and Cicer arietinum from Haryana, India. A total of 355 bacterial endophytes were screened for plant growth promoting traits. Out of all, 96 bacterial endophytes were selected based on morphological characters and multi-PGP traits, and their diversity analyzed by amplified ribosomal DNA restriction analysis. Based on their ARDRA profile, the 25 representative isolates (12 from P. sativum and 13 from C. arietinum), were selected and identified by 16S ribosomal DNA sequencing. Genetic relatedness based on BLAST analysis revealed the similarity of these isolates with members of three prominent phyla, that is, Proteobacteria, Firmicutes, and Actinobacteria. The dominant cluster, Firmicutes, constituted 60% of the isolates, assigned to four different genera, Bacillus, Staphylococcus, Ornithinibacillus, and Lysinibacillus. Phylum α-proteobacteria included two genera, namely Paenochrobactrum and Ochrobactrum and three genera in phylum γ-proteobacteria, namely Pseudomonas, Pantoea and Proteus. The phylum Actinobacteria was constituted of two genera, Microbacterium and Arthrobacter. Bacillus zhangzhouensis, Bacillus safensis, Arthrobacter enclensis from P. sativum and Bacillus haynesii, Paenochrobactrum sp. from C. arietinum are documented as plant growth promoting endophytic bacteria for the first time in the present study. The in vitro and in vivo assessment based on bonitur score revealed that the endophytic isolates Bacillus mojavensis PRN2, Pseudomonas chlororaphis PHN9, B. safensis PRER2, Pseudomonas sp. RCP1, Pseudomonas lini PRN1 and B. haynensii RCP3 from P. sativum and C. arietinum significantly enhanced the plant growth parameters. Therefore, these potential isolates can be further harnessed for preparation of bioformulations to enhance sustainable agriculture.
Topics: Bacteria; Cicer; DNA, Ribosomal; Endophytes; Firmicutes; Pisum sativum; Phylogeny; Plant Roots; Proteobacteria; RNA, Ribosomal, 16S
PubMed: 35655367
DOI: 10.1002/jobm.202100575 -
Letters in Applied Microbiology Jul 2023The use of microbial consortia has become a promising alternative for the management of various diseases. In this study, 18 artificial consortia were designed,...
The use of microbial consortia has become a promising alternative for the management of various diseases. In this study, 18 artificial consortia were designed, consisting of five bacteria, five fungi, and a mixture of five fungi and five bacteria; from a collection of microorganisms isolated from the rhizosphere of cape gooseberry plants grown in two soils potentially suppressive against Fusarium oxysporum. When evaluated under greenhouse conditions for their biocontrol activity on cape gooseberry plants, one consortium was selected for their high efficacy (over 90%) in the control of vascular wilt caused by F. oxysporum f. sp. physali. This was constituted by 10 microorganisms, the bacteria Paenibacillus peoriae, Bacillus subtilis, Lysinibacillus sp., B. simplex, and Pseudomonas chlororaphis; and the fungi Beauveria bassiana, Scopulariopsis brevicaulis, Trichoderma gamsii, T. ghanense, and T. lignicola. On the other hand, four of the consortia evaluated in the presence of the pathogen mitigated the deleterious effect produced by the pathogen on plant growth, expressing higher dry weights, both in the aerial and root parts. This work represents the first report on using these mixtures of microorganisms to control vascular wilt produced by F. oxysporum. However, further studies are needed to determine their activity in cape gooseberry fields.
Topics: Fusarium; Microbial Consortia; Ribes; Physalis; Bacillus subtilis; Fungi; Plant Diseases
PubMed: 37348479
DOI: 10.1093/lambio/ovad072 -
Microorganisms Sep 2021The bacterial pathogen causes the destructive fruit blotch (BFB) on cucurbit plants. YL-1 is a bacterial strain isolated from Mississippi soil and its genome harbors...
The bacterial pathogen causes the destructive fruit blotch (BFB) on cucurbit plants. YL-1 is a bacterial strain isolated from Mississippi soil and its genome harbors some antimicrobial-related gene clusters, such as phenazine, pyrrolnitrin, and pyoverdine. Here, we evaluated the antimicrobial activity of strain YL-1 as compared with its deficient mutants of antimicrobial-related genes, which were obtained using a based site-specific mutagenesis strategy. We found that only phenazine-deficient mutants Δ and Δ almost lost the inhibitory effects against in LB plates compared with the wild-type strain YL-1, and that the main antibacterial compound produced by strain YL-1 in LB medium was phenazine-1-carboxylic acid (PCA) based on the liquid chromatography-mass spectrometry (LC-MS) analysis. Gene expression analyses revealed that PCA enhanced the accumulation of reactive oxygen species (ROS) and increased the activity of catalase (CAT) in . The inhibition effect of PCA against was lowered by adding exogenous CAT. PCA significantly upregulated the transcript level of from 6 to 10 h, which encodes CAT that helps to protect the bacteria against oxidative stress. Collectively, the findings of this research suggest PCA is one of the key antimicrobial metabolites of bacterial strain YL-1, a promising biocontrol agent for disease management of BFB of cucurbit plants.
PubMed: 34683333
DOI: 10.3390/microorganisms9102012